The invention relates generally to computers interconnected for communication over a network such as the Internet and intranets, and more particularly to a distributed computer-based system for coordinating and otherwise maintaining data pursuant to a distributed data model.
The Internet has established a dynamic, public environment for communication and interaction among its millions of users. In business, the Internet has redefined vendor-manufacturer, manufacturer-distributor, distributor-customer, and other relationships. With extension of the Internet technology into internal, secured networks of individual companies, the xe2x80x9cintranetxe2x80x9d or xe2x80x9cprivate Internetxe2x80x9d, as it is called, has enabled new forms of document and information sharing between individual employees and work groups using company directory and network infrastructure. Online services, such as electronic bulletin boards and chat rooms, electronic commerce, and technical support for products, are available on the World Wide Web (xe2x80x9cWWWxe2x80x9d or xe2x80x9cWebxe2x80x9d) operating over the Internet.
The Internet has, at its core, a server-client architecture, in which individual clients (i.e., Internet-content users) interface via computer-executable applications such as browsers with servers (i.e., Internet-content providers) to obtain documents from Web sites. Browsers are software programs that enable personal computers to request, receive (e.g., download), interpret, and present Internet documents, and generally navigate the Internet. Web servers typically have standard interfaces for running external programs, the most common is the Common Gateway Interface (CGI). Web sites are collections of documents, usually consisting of a home page and related, linked documents, located on servers remote from the client. The documents can be compound documents, containing data, graphics, video, sound, and/or other types of media, as well as links to other documents. Essentially, the WWW is a web of interconnected documents, or, more precisely, document objects that are located at various sites on the Internet.
Among the types of document objects on the WWW are documents and scripts. A script is an executable program, or a set of commands stored in a file, that can be run by a Web server to produce a document that is then returned to the Web browser. Typical script actions include running library routines or other applications to get information from a file or database, or initiating a request to get information from another computer, or retrieving a document corresponding to a selected hypertext link. A script is run on the Web server when, for example, a user selects a particular hypertext link in the Web browser.
Underlying the Internet technology are advances in standardization, including personal computer hardware, software, network protocols, and infrastructural conventions (such as the xe2x80x9cUniform Resource Locatorxe2x80x9d or xe2x80x9cURLxe2x80x9d). URLs provide location addresses for all document objects on the WWW. A URL uniquely references a document object and often defines an access algorithm using Internet protocols.
xe2x80x9cInternet protocolsxe2x80x9d, as that expression is used herein, are defined as current or future language conventions and present or future communication protocols that are generally-accepted and used for generating messages including documents for transmission over the Internet, or for transmitting such messages over the Internet, respectively. Such language conventions include, for example, at present, Hypertext Markup Language (xe2x80x9cHTMLxe2x80x9d) and eXtensible Markup Language (xe2x80x9cXMLxe2x80x9d). Such communication protocols include, for example, at present, Hypertext Transfer Protocol (xe2x80x9cHTTPxe2x80x9d), TCP/IP, FTP, GOPHER, NetB/os, SPX/IPX(trademark) and AppleTalk(trademark). A primary requirement of the communication protocol is that it supports the establishment of reliable or unreliable directed sessions between addressable network devices. Those skilled in the art will be familiar with these language conventions and protocols.
HTML is a language used for writing hypertext documents, containing multimedia content and links to other documents. An HTML document includes a hierarchical set of markup elements, where most elements have a start tag, followed by content, followed by an end tag. Tags are enclosed in angle brackets (xe2x80x9c less than xe2x80x9d and xe2x80x9c greater than xe2x80x9d) and indicate how the document is structured and how to display the document, as well as destinations and labels for hypertext links. There are tags for markup elements such as titles, headers, text attributes such as bold and italic, lists, paragraph boundaries, external links to other documents, and internal links to other parts of the same document, graphic images, and many other document features. Many books are in wide circulation regarding programming using HTML.
XML is another of the language conventions included in the Internet protocols. XML is compatible with and complementary to HTML, at least in its current version. It is a standard way of describing a class of data objects as stored in computers, called XML documents, and behavior of programs that process these objects. XML documents are made up of storage units called entities, which contain either text or binary data. Text is made up of characters, some of which form the character content of the documents, and some of which forth markup. Markup encodes a description of the document, such as its storage layout and logical structure. A software module called an XML processor is used to read XML documents and provide access to their content and structure. Further information regarding XML can be had with reference to Version 1.0 of the XML specification, available at  less than HTTP://www.w3.org/XML greater than , and incorporated herein by reference.
A Web server and a Web browser communicate typically using the HTTP message protocol and the underlying TCP/IP data transport protocol of the Internet. In HTTP, the Web browser establishes a connection to a Web server and sends an HTTP request message to the server. In response to the request message, the Web server checks authorization, performs any requested action such as downloading a document identified by its URL, and returns an HTTP response message containing either the HTML document resulting from the requested action or an error message. The returned document may simply be a static file stored on the Web server, or it may be generated dynamically using a script called in response to the request message.
Networks using the TCP/IP protocol route messages based on Internet Protocol (IP) addresses of the destination devices. The IP addresses comply with a specified format, currently including a 32-bit numeric address written as four numbers separated by periods. Each device on a network has a unique IP address used for communication over the network. The term xe2x80x9cIP addressxe2x80x9d as used hereinbelow is intended, depending on context, to encompass addressing in compliance with current or future Internet protocols.
To take advantage of the Internet, tools and resources have been developed in compliance with the Internet protocols, including company-critical applications such as e-mail. E-mail is electronic mail, by means of which documents are sent and, received electronically at selected addresses. It has been estimated that a vast majority of Internet-based interaction is through the use of e-mail and other browser-based media that follow a xe2x80x9cdocument send and receivexe2x80x9d model. Perhaps due to that model, users often view the Internet as inherently xe2x80x9cpeer-to-peerxe2x80x9d, with individuals accessing documents provided by other individuals, without intervention by a higher authority.
The Internet is dynamic and flexible in providing users with entertaining and useful ways of communicating, though it does not meet all the needs of users. While users interact increasingly through the Internet, they continue to interact xe2x80x9coffxe2x80x9d of the Internet in more conventional ways, such as through multi-medium (phone, fax, whiteboard), multi-temporal (real-time, overnight mail) and other informal means of communication.
It would be desirable to extend the Internet paradigm to personal and private communications and other shared and mutual activities between individuals and small groups in shared private spaces. Such interactions should preferably occur instantly, directly, and confidentially between participants"" personal computers, or other network-capable devices, without exposing such interactions to server bottlenecks through which Internet traffic is typically funneled to third-party Web sites where communications can be intercepted and confidences violated.
It would also be desirable to provide a technique that allows users at various remote sites to share and edit documents on a peer-to-peer basis, while maintaining consistent copies of the documents at local sites. Such a technique should permit any of the users to issue change requests regarding the documents, which changes can then be made asynchronously to the copies at all the local sites in a coordinated fashion even if the sites are disconnected from the network when the change requests are issued.
The invention resides in an apparatus called an activity, which is operable in a personal computer system, communication appliance or other network-capable device, for performing a shared, focused task with other, remotely-located users, such as, for example, a xe2x80x9cchatxe2x80x9d, gaming, or business application. The activity includes a tool for causing generation of data change requests, called deltas, responsive to user interactions. The activity also has a data-change engine for maintaining data in preferably non-volatile, persistent memory pursuant to a data model. The data-change engine includes a tool end for receiving deltas from the tool, providing the deltas with activity-specific commands for carrying out the request, and providing notification to the tool of data changes caused by delta execution. The data-change engine also includes a dynamics manager end for receiving, from a dynamics manager, data-change directions to execute the deltas, i.e., perform the deltas"" commands to make the requested changes to the data.
In another aspect, the invention resides in a system for providing communications and other shared and mutual activities between individuals and small groups in shared private spaces, called xe2x80x9ctelespacesxe2x80x9d. In the system, participants or members of a telespace interact through network-capable devices, which can communicate with one-another over a network, e.g., the Internet or an intranet, and store individually local copies of telespace data. Each telespace is an instantiation of one or more activities operable on each of the network-capable devices of members of the telespace. Each activity:includes one or more tools for initiating data change requests or deltas responsive to telespace member interactions. Each activity also includes one or more data-change engines, separate from the tools, for maintaining the local copy of telespace data pursuant to a common data model. The data model is, for example, activity-specific, and preferably telespace-wide. Each network-capable device also includes a dynamics manager for locally generating deltas, for, responsive to the deltas, directing the data-change engine to execute the deltas by making the requested changes to the local copy of data, and for coordinating the execution of deltas from the various network-capable devices.
In yet another aspect, the invention can be practiced in a networked system including plural, preferably network-capable devices at different locations connected for communication preferably in accordance with Internet protocols. Each network-capable device has (a) a memory for storing a local copy of activity-related data pursuant to a common data model, (b) one or more activities each including one or more tools and corresponding data-change engines as described above, (c) a communications manager for causing deltas to be shared among all the network-capable devices of the networked system that participate in the telespace to which the deltas pertain; and (d) a dynamics manager for coordinating execution of both locally-generated and remotely-generated deltas. The user interactions can be initiated, and the resulting deltas generated, at any of the network-capable devices of the networked system, and the deltas are transmitted to each of the devices preferably over the network. The dynamics managers direct the operation of their local data-change engines, preferably to prioritize execution of deltas and to maintain substantial consistency of the data across the networked system. The networked system thus allows users at various remote sites, e.g., to share and edit data or perform other activities independently, on a peer-to-peer basis, while maintaining substantially consistent copies of the data at each of the network-capable devices for use even when disconnected from the network.
In still another aspect, the invention can be implemented as an activity-based collaboration (ABC) system for interpersonal interaction. The ABC system includes plural, network-capable devices connectable, e.g., via public networks (e.g., the Internet or wide area networks (WANs)) or via private networks (e.g., local area networks (LANs) or intranets), by cable, fiberoptics, infrared (IR) or other forms of communication links, to form the above-described networked system. Each network-capable device is equipped with the above-described memory, and a framework including one or more dynamics managers. The network-capable devices are preferably plug-compatible with the public network infrastructure, personal desktop applications and infrastructure (sometimes called xe2x80x9cpersonal Internetsxe2x80x9d), and, where applicable, a company intranet. The ABC system preferably uses dynamic, snap-in activity components, each for performing a specific task, such as xe2x80x9cchatxe2x80x9d, document editing, gaming, etc. The activity components can comprise software made available, for example, as shrink-wrapped products or downloaded over the network, e.g., the Internet. The activity components can operate through common application programming interfaces (API) with the framework. Accordingly, the framework can be viewed and function as a platform for applications in the form of the activity components.
Yet another aspect of the invention resides in the framework further including a communications manager operable on a local network capable device for sending locally-generated deltas to remote network-capable devices and for receiving remotely-generated deltas from the remote network-capable devices. The communications manager can selectively send the local deltas either directly to the remote network-capable devices, e.g., at their respective URLs, or to a xe2x80x9cstore and forwardxe2x80x9d relay, e.g., at its URL, in response to network connection status information regarding the remote network-capable device. The network connection status information can include connectability information maintained by the communications manager, including, e.g., information regarding communication protocol compatibility, security issues (e.g., firewalls) that may render the remote device unreachable by the local device. The connection status information can also include information maintained by a presence mechanism, such as a presence server, regarding the online/offline status of the remote device. The presence server can be part of the ABC system, and, e.g., responsible for sending the online/offline status information over the network to the communications manager. In situations where the remote network-capable device is temporarily not connected to the network (xe2x80x9cofflinexe2x80x9d), the relay can store the deltas until notified that the remote network-capable device has reconnected to the network, and then send the deltas to the reconnected remote network-capable device. For receipt of deltas from the remote network-capable devices, the communications manager sends an online/offline status notification to the presence server indicating whether the local network-capable device is connected to the network (xe2x80x9conlinexe2x80x9d) and therefore capable of receipt of deltas from remote devices.
Thus, the invention can be implemented as separate commercial products and services, including provision of the individual activity components, the framework for individual network-capable devices, and/or networked or ABC system, as well as communication services for effecting interactions between devices forming the system.